This invention relates generally to seals and gaskets and methods of producing same, and more particularly to an automotive seal that is especially suited for preventing leakage therethrough and to a novel method of producing such a seal.
Gaskets and/or seals are well known in the art. In this regard, reference can be made to any of the following U.S. patents as representative prior art in this area: U.S. Pat. No. 3,186,042 to Daley; U.S. Pat. No. 4,443,517 to Shah; U.S. Pat. No. 4,601,476 to Usher et al.; U.S. Pat. No. 4,659,091 to Baasner et al.; and U.S. Pat. No. 4,756,561 to Kawata et al. Although each of the foregoing patents disclose gaskets and/or seals that are suitable for their intended purpose, there is presently a need in the automotive industry for a structure that prevents leakage when used on an automobile exhaust system.
The high temperature, composite structure disclosed herein addresses this need, as well as other related needs.
In general, the present invention is directed to a high temperature, composite structure comprising a blank of wire mesh material fabricated from drawn wire from a stainless steel rod. The drawn wire is annealed and knitted to create the blank of wire mesh material, the blank of wire mesh material having voids formed therein. A dispersion comprising vermiculite as a binder is impregnated within the blank of wire mesh material. The dispersion substantially fills the voids of the blank of wire mesh material. Preferably, the blank of wire mesh material will fill a volume of 20% to 70% of a preform prior to it being impregnated by the dispersion.
A method of manufacturing the structure comprises the steps of: (a) providing a blank of wire mesh material having voids formed therein; (b) impregnating the blank of wire mesh material with a dispersion consisting of vermiculite as a binder, the dispersion substantially filling the voids; (c) eliminating a water fraction of the dispersion; and (d) pressing the impregnated blank of wire mesh material to a desired shape and density.
More particularly, the step of providing a blank of wire mesh material comprises the steps of drawing wire from a stainless steel rod, annealing the drawn wire, mixing, and knitting the drawn wire to create said blank of wire mesh material. Prior to the impregnating step, the method further comprises the step of preforming the blank of wire mesh material into a first predetermined shape. The blank of wire mesh material can further be impregnated at least one more time.
Accordingly, among the several objects of the present invention are: the provision of structure that is capable of preventing leakage when used on an automobile exhaust system; the provision of such a structure that is capable of withstanding relatively high compression forces applied thereon; the provision of such a structure having chemical and physical characteristics which prevent it from degrading under high temperature; the provision of such a structure that is easy to install during the assembly of the automobile exhaust system; the provision of such a structure that is capable of withstanding axial, radial and shearing forces; and the provision of such a structure that is cost-efficient to manufacture.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds.